1. Field of the Invention
This invention relates generally to filters and filter apparatus. More particularly, the present invention relates to filtration and/or separation apparatus. Most particularly, the invention relates to a stacked conical filtration or separation apparatus.
2. Discussion of the Related Art
The advantages of a conical shaped filtration apparatus are known in the art. The conical configuration allows for lower velocity of the primary phase fluid in the area between the outside surface of the coalescing element or elements and the filter assembly inner wall thereby reducing the maximum droplet diameter which may be supported by or re-entrained in the primary phase fluid. This allows for more efficient separation of the coalesced droplets from the primary phase fluid. It also allows for lower pressure drop through the filter elements.
U.S. Pat. No. 2,823,760 to Soran K. Andersen discloses a water separator which relates generally to apparatus for separating liquids from gases or gaseous fluids, and more particularly, to apparatus for removing particles of a liquid such as a water from a gaseous fluid such air. The invention has particular utility in air conditioning systems such those employed for conditioning air delivered to air craft cabins and the like. A conically shaped condenser is positioned within a housing 11. The condenser includes a conical body portion 16, the larger end of which is provided with a radially outwardly extending flange that is positioned adjacent the flange on the housing. The cone of the condenser body portion is more obtuse than the cone of the housing 11. The condenser is thus in a spaced relationship to the inner surface of the housing, with the smaller end of the condenser being a greater distance from the housing than the larger end thereof.
U.S. Pat. No. 5,454,945 entitled xe2x80x9cCoalescing Filter and Assemblyxe2x80x9d, (and continuation Ser. No. 08/414,273) in the name of Michael R. Spearman, one of the applicants herein, shows a porous coalescing filter element of conical or frustroconical configuration disposed within a cylindrical filter housing such that the area between the element and the wall increases in the direction of the primary phase flow to keep the annular velocity substantially constant or decreasing in the direction of primary fluid flow. The element may be manufactured with a round end and tapered walls terminating to a pointed apex, but is more preferably manufactured and secured within the filter housing using flat end caps on both ends. The filter element may be vacuum formed or manufactured from media in a flat sheet form which may be pleated if desired. The specification of said U.S. Pat. No. 5,454,945 is specifically incorporated herein by reference.
It has been found under some conditions, that the surface area available from a conical configuration is not as great as expected. Thus, those skilled in the filtration art continued to search for a conically shaped filtration and/or separation apparatus with increased surface area.
A conically shaped filtration and/or separation apparatus is provided which is constructed from a stack of filters, at least some of which are different sizes, superposed above each, other, of said plurality of filters in a fluid communicable relationship.
It was found by using this construction that an extremely high surface area to volume ratio could be obtained while still obtaining the benefits of the conical shape. The high filtration surface area to volume ratio results in higher performance filter elements than the prior art in the areas of pressure drop efficiency and capacity. In addition, the compact design is easy to handle and the collapsible embodiment results in lower shipping and disposal cost. Constructions embodying a stack of tubular shaped filters are known in the prior art from the U.S. Pat. No. 5,443,724 to Willimson et. al., but there are no known patents showing a conically shaped filter made by a stack of tubular or other shaped conventional filters.
In one embodiment of the present invention, a conically shaped filter element includes a plurality of filters of finite, different, sizes, each of said plurality of filters superposed above each, other, of said plurality of filters in order of decreasing size in a fluid communicable relationship.
In another embodiment of the invention, a stacked, hour glass shaped filter element is provided, including a plurality of filters of finite, different, sizes, each of said plurality of filters superposed above each, other, of said plurality of filters, first in order of decreasing diameter, and then in order of increasing diameter, in a fluid communicable relationship.
In a further embodiment of the invention, a stacked filter element is provided including a plurality of filters of different sizes, at least one of said plurality of filters being of a different size than any of the rest of said plurality of filters, and at least one of said plurality of filters being made of a different media than any of the rest of said plurality of filters, each of said plurality of filters superposed above each, other, of said plurality of filters in a fluid communicable relationship.
In another embodiment of the present invention, a filter assembly comprising a stacked separation and/or coalescing filter element is provided, including means for introducing the fluid to be filtered into the interior of said filter element at the inside thereof such that the fluid will flow from the inside to the outside of the filter element, and wherein said filter element has its end substantially closed by a pair of closure members, and is mounted inside a suitable filter housing having inlet means sealingly communicating with the interior of said filter element, and outlet means communicating with the atmosphere.
In yet another embodiment of the present invention, a collapsible conical filter and/or separator element is provided including a plurality of filters of different sizes, said filters being chosen such that the outside diameter of each of said plurality of filters will be substantially the same as the inside diameter of the next larger of said filters so that each of said filters will fit inside one of the others of said plurality of filters when arranged in order of increasing size. Each of said plurality of filters, except for the largest and smallest of said filters, including a filter media of a predetermined size, an upper end cap potted onto said filter media, and a lower end cap potted onto the lower end of said filter media.
In a further embodiment of the present invention, a tubular filter element is provided, said tubular filter element including a filter tube, an upper end cap sealingly attached to the upper end of said filter tube, said upper end cap including a central opening to provide for fluid communication, a downward facing annular groove in sealing communication with the upper end of said filter tube, and a second or female portion of a connecting means to be engaged by a first or male portion of a connecting means on a lower end cap on another filter element. A lower end cap is provided which is sealingly attached to the lower end of said filter tube, said lower end cap including a central opening to provide for fluid communication, an upwardly facing annular groove in sealing communication with the lower end of said filter tube, and a first or male portion of a connecting means to engage a second or female portion of a connecting means on an upper end cap on another filter element.
Therefore, it is an object of the present invention to provide an improved, conically shaped, stacked, filter and/or separator.
A further object of the present invention is to provide a conical filter and/or separator having a high surface to volume ratio, and compact design.
A still further object of the present invention is to provide a collapsible conical filter or separator which is easy to handle and results in lower shipping and disposal costs.